Phage display services for antibody discovery

Phage Display form

    Accelerate your monoclonal antibody development program with ProteoGenix antibody phage display services and get your antibodies in less than 2 months! Our naïve libraries consist of antibodies from various species and in various formats (Fab, scFv, or VHH), easily adapted to recombinant monoclonal antibody production. Benefit from our strong guarantees and receive at least 3 relevant binders with high affinity and screened in the application of your choice (ELISA, WB, or Flow Cytometry). Thanks to our highly diversified libraries and vast experience in phage display earned through more than 250 projects, we help you develop new antibodies for therapy, research, and diagnostics.

    Our solutions for antibody phage display


    Antibody phage display for therapeutic applications

    Developing therapeutic antibodies?

    Our high diversity human libraries ensure you receive the best binders for clinical applications forgoing the need for antibody humanization, and our VHH library grants you the ability to target even the most cryptic epitopes. Our approach to antibody phage display for therapeutic applications is also focused on giving you an edge in oligoclonal antibody development (i.e., antibody cocktails) and next-generation envenoming therapies.


    Antibody phage display for diagnostic applications

    Developing diagnostic antibodies?

    Our process of antibody phage display for diagnostic applications is ideal for the generation of extremely sensitive and selective antibodies (i.e., rabbit antibodies) for diagnostics, food, and environmental monitoring applications. Forgoing the need for immunization, researchers can easily generate antibodies in the most diverse formats even against toxic or non-immunogenic antigens.

    Why choose ProteoGenix' antibody
    phage display services?

    Binders guaranteed
    Binders guaranteed

    Always receive AT LEAST 3 unique binders against your antigen!

    IP free antibodies in phage display
    IP free

    You get the full ownership of the antibody sequence generated!

    Best high diversity libraries for phage display
    Very high diversity antibody phage display libraries

    Our premium libraries contain at least 1010 different variants!

    scFv, Fab, and VHH antibodies in phage display
    scFv, Fab or VHH formats available

    The variety of our libraries allows us to propose a wide range of formats to fit a wide range of applications.

    Wide variety of species available in antibody phage display
    Wide variety of species available

    Mouse, sheep, llama, rabbit monoclonal antibodies etc. As well as our naïve libraries, you can also choose to develop immune libraries from a species of your choice without limitation.

    Short lead times in antibody phage display
    Save time!

    From antigen to antibody in less than 7 weeks!

    No animal use in antibody phage display
    No animal use

    Naïve library screening does not require any animal use.

    Buy your antibody library for phage display
    Buy your library

    Buy our naïve libraries or your own immune libraries!

    Naïve or immune antibody phage display libraries?

    Naïve libraries Immune libraries
    Species Human, rabbit, camelids (camel, llama, alpaca) No limitation except humans
    Formats Fab, scFv, VHH Fab, scFv, VHH
    Number of binders ++ +++
    Affinity of binders ++ +++
    Potential immunogenicity issues No Yes
    Animal use No Yes
    Timelines 4-5 weeks 11-16 weeks + 4-5 weeks
    Price + ++


    Antibody library generation is a vital first step in all phage display projects. The process encompasses the recovery of the naïve or immune antibody repertoire from specific host species by harvesting their B lymphocytes (B cells) or isolating PBMCs (peripheral blood mononuclear cells) by density gradient centrifugation of blood samples. The diversity of these repertoires is subsequently seized by mRNA extraction, cDNA synthesis, and PCR-mediated amplification of antibody-encoding genes.

    Naïve libraries are prized for their versatility (adaptability to different projects/antigens) while immune libraries are considered more labor-intensive and reserved for especially challenging projects aiming to boost antibody affinity and selectivity.

    Interested in our naïve library screening service or in constructing an immune library? Please feel free to contact our dedicated account manager.

    Find your perfect antibody phage display library!

    Library Format Species Size (clones)
    LiAb-SFCOVID-19TM scFv Human – Donors that recovered from COVID-19 – Ideal for the identification of SARS-CoV-2 binders 1.19 X 1010
    LiAb-SFMAXTM scFv & Fab Human – 5 different ethnic groups – 368 donors for maximized diversity 5.37 X 1010
    LiAb-SFaTM scFv Human 1.5 X 109
    LiAb-FabTM Fab Human 2.00 X 1010
    LiAb-VHHMAXTM VHH Camel, llama, alpaca – 57 animals – Ideal for nanobody generation 1.51 X 1010



    scFv & Fab Dog – 6 different breeds for maximized diversity 1.05 X 1010
    LiAb-SFRabTM scFv & Fab Rabbit – 4 different breeds for maximized diversity 1.09 X 1010
    LiPep-12TM Peptide 12-mer / 1.00 X 109
    LiPep-7TM Peptide 7-mer / 1.00 X 109


    ProteoGenix developed a large choice of proprietary phage display libraries that you can adapt to all your projects. Our goal is to fulfill all your unique requirements and to always push the boundaries of innovation by creating new and better phage display libraries. Whether you need a fully human antibody or a nanobody for therapeutic applications or a high-affinity rabbit antibody for diagnostic applications, our libraries will help you overcome your most difficult challenges. Feel free to contact our account manager for more information.

    Our antibody phage display service process

    Antigen design and production for antibody phage display
    Antigen procurement or design and production
    • Peptide/small molecules: conjugation to carriers
    • Protein production including gene synthesis
    • Cell overexpressing target protein

    Immune library

    Immune library

    Naive library

    Immune library construction for antibody phage display
    Immune library construction
    • PBMC isolation
    • RNA extraction and cDNA synthesis
    • VH and VL PCR amplification
    • Library construction and QC
    Library screening and biopanning in antibody phage display
    Library screening and biopanning
    • Screening of naive or immune library against antigen
    • 4-6 rounds of biopanning
    ELISA screening of single binders in antibody phage display
    ELISA screening of single phage binders
    • ELISA screening and validation until identification of at least 3-10 different binders
    DNA extraction and sequencing in antibody phage display
    DNA extraction & antibody sequencing

    Our antibody phage display service content

    Step Content Timelines Deliverables
    Library construction (only for immune libraries)
    • Animal immunization and titer tests
    • Cell isolation (spleen, bone marrow, PBMC)
    • RNA extraction
    • cDNA synthesis
    • VH and VL PCR amplification
    • cDNA assembly
    • Phagemid synthesis and cloning
    • Library QC
    11-16 weeks
    • Progress report
    Library screening and biopanning
    • Screening of the naïve or immune library
    • 4-6 rounds of biopanning
    4-5 weeks
    • Progress report
    ELISA screening
    • Screening and validation by ELISA until at least 3-10 different binders are identified
    • Progress report
    DNA extraction and antibody sequencing
    • Phage DNA extraction and antibody sequencing
    • Detailed report
    • DNA sequence of the best binder
      Full ownership of the sequences
    Options available:
    • Additional screening of single phage clones by ELISA against a specific protein/peptide/small molecule/cell
    • Additional screening of single phage clones by WB
    • Additional screening of single phage binders by flow cytometry on cells
    • Assessment of the affinity of single phage binders
    • Panning against cells overexpressing antigen of interest with library depletion against control cell

    Satisfied antibody phage display customer testimonial

    “I requested ProteoGenix’s services for the generation of neutralizing anti-COVID-19 antibodies by Phage Display. They designed an optimised strategy for this purpose which led to great results, with 4 antibodies identified as cross-reactive and neutralizing against all the current variants of concerns.

    During the whole project, Proteogenix strived to ensure the best quality of their final deliverables, especially by including additional screenings against emerging variants as the pandemic evolved.

    Their proactivity was key to obtaining promising and relevant blocking antibodies in only a few months. I highly recommend them for both their level of expertise and the personalised service they offer.”

    Trident pharma

    Khelan Patel, Managing Director
    Trident Biopharm Solutions, London, UK

    “All three of the antibodies you delivered were reformatted into IgGs and worked well. Interestingly two were d1 binders, and one was a d1/d2 binder when we domain mapped them here. They were good “protein X” blocking antibodies. But none were “protein Y” blockers. They express reasonably well. Overall we are quite happy with them.”

    Satisfied antibody phage display customer

    Senior scientist at aTyr Pharma, USA

    “ProteoGenix has been generous and sincere in supporting an academic laboratory like ours. They were able to identify several antibody sequences via phage display against a protein antigen and they screened twice more phages than initially planned to help us succeed in our project. ProteoGenix team was reactive and diligent in their replies and services.”

    nanyang university

    Alvin Chew, Research Fellow, Nanyang Technological University, Singapore

    “We are developing a novel immunotherapy and needed a highly potent monoclonal antibody. Currently the development of a novel antibody requires lengthy and expensive humanization process. We thus decided to screen for binders a human antibody library via phase display screening instead of humanizing a murine antibody. Proteogenix proposed just that. We provided our purified target antigen and in only one month several high affinity binders were obtained. We were able to quickly clone and produce a monoclonal antibody from the sequences provided. What should have taken 6 to 8 months was done in 2 for a fraction of the cost and for an equivalent quality.”

    nanyang university

    Dr Abbas El Sahili, Senior Research Fellow, Nanyang Technological University, Singapore

    “I requested ProteoGenix’s services for the generation of antibodies against a malarial protein by phage display. Their naive human library, which is comprised of 368 donors, is a unique resource which was one of the criteria I used to select their company. They optimized their standard screening strategy to be able to identify two specific clones, that they then expressed with very high yields in their proprietary XtenCHOTM cell line. I highly appreciated their level of expertise and their commitment to go beyond expectations, and I would recommend them for their reactivity and the high quality of their services.”

    brown university

    Prof Jonathan Kurtis, MD, PhD, Chair, Department of Pathology and Laboratory Medicine, Brown University, USA

    “We requested ProteoGenix’s services for the development of a monoclonal antibody for flow cytometry. They were able to identify three candidates that all bound well and specifically to our antigen. The best one was validated in our final application and the results were published in an international journal. We were overall satisfied with the quality of the final product and its results.”

    Tromso logo

    Dr Lorena Arranz, Group Leader, UiT the Arctic University of Norway, Tromsø – NCMM Associate Investigator – SFF Center Director

    “We requested ProteoGenix’s services for the development of antibodies against a specific surface protein by phage display. Their naive human library was built from 368 donors for maximized diversity. This unique quality and their reactivity convinced us to work with them. They successfully identified various candidates that all bound well and specifically to our antigen. I appreciated their expertise for the high quality of their services as well as their good responses to my questions for this project.”


    Naoya Uchida M.D., Ph.D. at The Institute of Medical Science, The University of Tokyo in Japan

    “We have been working together with ProteoGenix since 2020. Using phage display, they helped our team to develop several antibodies with effective blocking effects. We are pleased with their services and look forward to continue working together with them as we advance our research and bring the biologics to clinical stage.”


    Prof Johnny Ong Chin-Ann, MD, PhD, Group leader, National Cancer Centre, Singapore

    Case study: antibody generation against a small molecule by phage display

    Project requirements

    One of our customers requested a human antibody against a small molecule. The small molecule was conjugated to different carriers to achieve optimal coating. Biopanning was performed using our human naive library of high diversity.

    A total of 192 single phage binders were screened and validated by ELISA. 10 antibody sequences were required.

    Biopanning results

    Rounds Phage input (pfu) Phage output (pfu)
    Panning with antigen coating Panning with no coating (negative control)
    1 2.0×1012 8.9×106 3.4×106
    4 1.0×1012 4.0×107 2.5×106

    There is an obvious enrichment in anti-antigen binders even if it is difficult to remove the binders to carriers (known phenomenon).

    Polyclonal phage ELISA

    Phage quantity (pfu/well) Round 3 Round 4
    Antigen Control Antigen Control
    6×1012 3.035 2.584 3.630 3.451
    2×1012 2.798 1.709 3.308 3.007
    6.7X1011 1.508 1.069 3.028 2.128
    2.2×1011 0.5666 0.5024 2.976 1.885
    7.4×1010 0.1712 0.1932 2.581 1.704
    2.5×1010 0.08020 0.09040 2.033 1.317
    8.2×109 0.06090 0.09140 1.931 1.054
    2.7×109 0.01620 0.01740 0.7235 0.7526
    9×108 0.01290 0.01460 0.2341 0.2432

    Although there are many unspecific binders (known phenomenon), an obvious enrichment in anti-antigen binders is observed (data in bold).

    Monoclonal phage ELISA of the 11 unique antibodies identified (unique means unique sequence)

    Clones Ag-carrier 1 Ag-carrier 2 Ag-carrier 3 No coating Carrier 1 Carrier 2 Carrier 3
    A6 4.698 4.743 4.466 0.118 0.100 0.092 0.117
    A9 4.769 4.766 4.420 0.100 0.092 0.078 0.074
    B1 4.716 4.804 4.452 0.353 0.584 0.422 0.187
    B2 4.494 4.482 4.874 0.081 0.122 0.109 0.100
    D1 4.862 3.989 4.540 0.170 0.488 0.313 0.123
    D8 4.862 4.090 4.486 0.057 0.106 0.102 0.059
    F4 4.214 3.352 5.306 0.051 0.110 0.123 0.059
    H2 4.797 4.537 4.588 0.084 0.213 0.188 0.112
    H11 4.722 4.604 5.049 0.103 0.218 0.262 0.138
    1A11 4.407 4.528 4.562 0.054 0.086 0.115 0.079
    1G1 4.956 4.381 5.218 0.076 0.114 0.138 0.077

    We generated 11 unique clones that specifically and strongly bind to the small molecule antigen.

    Our customer decided to express these 11 clones as recombinant antibodies and to order the screening of 192 additional single phages, which resulted in the identification of 7 new unique sequences.

    Learn more about our capabilities of antibody phage display services. Discover our complete report by clicking on the “DOWNLOAD PDF REPORT” button.

    What is antibody phage display?

    The phage display technology encompasses the determination of interaction partners of a specific protein (protein-protein, protein-DNA, or protein-peptide). These interactions can subsequently be used as “bait” to capture phages displaying peptides, proteins, or antibodies encoded in high diversity DNA libraries. Through the interactions, it becomes possible to determine the function of a specific peptide or protein.

    Phage display cycle: phage display library, panning/biopanning and validation by ELISA

    The phage display technique commonly employs filamentous phages such as phage M13 from Escherichia coli. This method has proven to be a powerful way to interrogate libraries containing billions of different proteins or peptides.

    The application of phage display on large antibody libraries has led to real success in the isolation of highly selective and specific monoclonal antibodies.

    The use of libraries composed of billions of antibodies displayed on phages offers a highly valuable and effective alternative to traditional methods of antibody generation by allowing the quick selection of the most relevant candidates for your research.

    M13 bacteriophage in antibody phage display

    All ProteoGenix’s antibody phage display libraries are made using the filamentous phage M13, a virus infecting the bacterium E. coli. M13 is a lysogenic phage, comprised of a circular and single-stranded DNA encased in a thin flexible tube coated by about 2700 copies of protein pVIII, the major coat protein, and about 5 copies of pIII, the minor coat protein, present at the ends of the tube.

    Infection with M13 plasmids is not lethal for bacteria and they are used for many recombinant DNA processes. Antibodies are generally displayed as fragments such as single-chain variable fragments (scFv), antigen-binding fragments (Fab), or variable heavy-chain antibody fragments (VHH or nanobodies).

    These fragments are typically fused to protein pIII and cloned into a phagemid vector, comprising a simplified version of phage M13 containing only the pIII-antibody fusion protein, an origin of replication, and a selection marker (e.g., antibody resistance gene).

    The phagemid vector is used in conjugation with a helper phage which, in turn, contains all essential elements of phage M13 except for a slightly defective origin of replication and no antibody fragments. The co-transformation of these two elements in E. coli results in the expression of hybrid phage particles generally displaying a single pIII-antibody fusion protein alongside native pIII proteins (essential for infection).

    The reduced abundance of antibodies displayed per phage particle ensures only the binders with the highest affinity are selected during the process of biopanning.

    Advantages of antibody phage display

    The key attribute of phage display is the physical coupling between genotype and phenotype where the phage displays an antibody fragment on its surface while encoding the corresponding gene in its genome. This allows the fast enrichment of antigen-specific binders and amplification in their corresponding host. The major advantage of the technique lies in the simplified structure, stability, versatility, and reliability of phages which can be adapted to various surfaces or even used for in vivo applications.

    Other advantages of phage display include:

    • Compatibility with toxic or non-immunogenic antigens (which cannot be used in hybridoma-based antibody discovery)
    • Ability to easily tailor antibody cross-reactivity, particularly useful when designing highly selective therapeutic or diagnostic applications (narrow cross-reactivity), or when developing complex envenoming therapies to target several closely related proteins venoms (wide cross-reactivity)
    • Easy and quick access to antibody sequences
    • When naïve high-diversity libraries are used, additional advantages include:
      • Reduced lead times (less than 7 weeks)
      • Minimization of animal use (no animal immunization is necessary)
      • Possibility of using the same antibody library in different projects (versatility)
      • Possibility of quickly generating oligoclonal therapies (antibody cocktails), invaluable in the fight against infectious diseases

    What are the applications of antibody phage display?

    Phage display comprises the study of protein-ligand interactions. For this reason, its applications are broad. When antibodies are displayed on the surface of phages, the process of selection can be used to:

    Other advantages of phage display include:

    • Discover novel antibody functions (antibody discovery) with multiple applications including therapeutic, diagnostic, research, or  catalytic antibody discovery
    • Engineer existing antibodies to increase their affinity towards a specific target and/or improve their biophysical properties and thus their developability

    Moreover, peptides can be displayed on the surface of phages and screened against a specific antibody. In this way, phage display can be used for epitope mapping applications. This is invaluable for the further development of highly selective therapeutic applications, such as oligoclonal therapies, or diagnostic applications, such as Sandwich ELISA which requires the use of an antibody pair targeting non-overlapping epitopes of a specific antigen.


    For additional resources, check all Frequently Asked Questions (FAQs) about phage display on our dedicated page.

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